WHITLOCK. — CRYSTAL FORMS OF CALCITE. 339 



Referred to N 3 this zone fragment is incomplete and contains the extra 

 forms ff and y . 



& (25 • 7 • 32 • 5) = (62 • 13 • 34) . This scalenohedron was observed 

 by Beykirch 118 on crystals from Dortmund, Prussia. This form falls 

 very close to (15-4- 19-3) = (37-8-20) and should possibly be referred 

 to the simpler indices. 



t» (10-3-13-2) = (25-5-14). This scalenohedron was recorded by 

 Sansoni 119 on crystals from Freiberg. In spite of the relatively high 

 normal series to which this form is referable, the fact that it lies in the 

 well marked zone [0441 : 8081] should class it as probable. 



scalenohedrons of the zone [1011 :2461] = [100 :313]. 



Symbol 7. 



Extended beyond the limits to be discussed this zone contains several 

 important knot points. Between (100) and 313) the forms are: 



N 2 - (7) (5) (j) • 1 1 



Referred to N 2 the zone fragment lacks the term 2 and contains the 

 extra forms 17, 13 and 8, the latter of which has been discussed under 

 zone 12. It is noteworthy that these three extra forms were observed 

 on one occurrence, i. e., crystals from Lake Superior, Mich. 



Z (16-4-20-15) = (17-1-3). This scalenohedron was observed 

 by Palache 120 on several crystals from Lake Superior. It was de- 

 scribed as_a somewhat rounded series of planes tending to pass into 

 2V(12-4-16-ll) = (13jl-3)._ It marks the intersection of zones 

 (0443 : 8443] and [1123 : 4041]. The form should be regarded as 

 fairly probable. 



N (12-4-16-11) = (13-1-3). This scalenohedron was also ob- 



118 Beykirch, J., Centralblat. f. Min., 2, 494 (1901). 



119 Sansoni, F.,Giorn. d. Min., 5, 72 (1894). 



120 Palache, loc. cit., Fig. 17. 



